This invention relates to antifungal antibiotics. In particular, this invention relates to adenine containing antibiotic compounds which are effective in vivo antifungal agents.
Although many antibiotics, for example, the penicillins and the cephalosporins, are highly effective in the treatment of bacterial infections, more effective agents in the treatment of systemic fungal infections are needed. Accordingly, the search for antibiotics effective in the treatment of systemic fungal infections of man and animals is the subject of a continuing research effort.
The antifungal agents of this invention were discovered as minor factors occurring in the fermentation broth of Streptomyces griseolus NRRL 3739. This microorganism is used in the production of the known antifungal antibiotic A-9145 as described by U.S. Pat. No. 3,758,681 issued Sept. 11, 1973. Following the discovery of the antibiotic A-9145, continuing development of isolation procedures for the antibiotic led to the discovery of the previously unrecognized minor factors which form the subject of this invention. The detection of the presence of the antifungal factors described herein was rendered difficult because of their low order of antibacterial and antifungal activity in standard in vitro tests.
In contrast to the antibiotic A-9145 which is active both in vitro and in vivo, the antifungal agents provided by this invention display minimal antifungal activity in vitro but are effective antifungal agents in vivo.